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  1. 19 11月, 2019 1 次提交
  3. 27 8月, 2019 1 次提交
  5. 01 7月, 2019 1 次提交
  7. 29 6月, 2019 7 次提交
  9. 12 6月, 2019 1 次提交
  11. 29 9月, 2018 1 次提交
    • D
      xfs: avoid lockdep false positives in xfs_trans_alloc · 8683edb7
      由 Dave Chinner 提交于 
      We've had a few reports of lockdep tripping over memory reclaim
context vs filesystem freeze "deadlocks". They all have looked
to be false positives on analysis, but it seems that they are
being tripped because we take freeze references before we run
a GFP_KERNEL allocation for the struct xfs_trans.

We can avoid this false positive vector just by re-ordering the
operations in xfs_trans_alloc(). That is. we need allocate the
structure before we take the freeze reference and enter the GFP_NOFS
allocation context that follows the xfs_trans around. This prevents
lockdep from seeing the GFP_KERNEL allocation inside the transaction
context, and that prevents it from triggering the freeze level vs
alloc context vs reclaim warnings.
Signed-off-by: NDave Chinner <dchinner@redhat.com>
Reviewed-by: NBrian Foster <bfoster@redhat.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
      8683edb7
  13. 03 8月, 2018 7 次提交
  15. 27 7月, 2018 3 次提交
    • B
      xfs: bypass final dfops roll in trans commit path · b277c37f
      由 Brian Foster 提交于 
      Once xfs_defer_finish() has completed all deferred operations, it
checks the dirty state of the transaction and rolls it once more to
return a clean transaction for the caller. This primarily to cover
the case where repeated xfs_defer_finish() calls are made in a loop
and we need to make sure that the caller starts the next iteration
with a clean transaction. Otherwise we risk transaction reservation
overrun.

This final transaction roll is not required in the transaction
commit path, however, because the transaction is immediately
committed and freed after dfops completion. Refactor the final roll
into a separate helper such that we can avoid it in the transaction
commit path.  Lift the dfops reset as well so dfops remains valid
until after the last call to xfs_defer_trans_roll(). The reset is
also unnecessary in the transaction commit path because the
transaction is about to complete.

This eliminates unnecessary regrants of transactions where the
associated transaction roll can be replaced by a transaction commit.
Signed-off-by: NBrian Foster <bfoster@redhat.com>
Reviewed-by: NBill O'Donnell <billodo@redhat.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NDarrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: NDarrick J. Wong <darrick.wong@oracle.com>
      b277c37f
    • B
      xfs: drop unnecessary xfs_defer_finish() dfops parameter · 9e28a242
      由 Brian Foster 提交于 
      Every caller of xfs_defer_finish() now passes the transaction and
its associated ->t_dfops. The xfs_defer_ops parameter is therefore
no longer necessary and can be removed.

Since most xfs_defer_finish() callers also have to consider
xfs_defer_cancel() on error, update the latter to also receive the
transaction for consistency. The log recovery code contains an
outlier case that cancels a dfops directly without an available
transaction. Retain an internal wrapper to support this outlier case
for the time being.
Signed-off-by: NBrian Foster <bfoster@redhat.com>
Reviewed-by: NBill O'Donnell <billodo@redhat.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NDarrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: NDarrick J. Wong <darrick.wong@oracle.com>
      9e28a242
    • B
      xfs: support embedded dfops in transaction · e021a2e5
      由 Brian Foster 提交于 
      The dfops structure used by multi-transaction operations is
typically stored on the stack and carried around by the associated
transaction. The lifecycle of dfops does not quite match that of the
transaction, but they are tightly related in that the former depends
on the latter.

The relationship of these objects is tight enough that we can avoid
the cumbersome boilerplate code required in most cases to manage
them separately by just embedding an xfs_defer_ops in the
transaction itself. This means that a transaction allocation returns
with an initialized dfops, a transaction commit finishes pending
deferred items before the tx commit, a transaction cancel cancels
the dfops before the transaction and a transaction dup operation
transfers the current dfops state to the new transaction.

The dup operation is slightly complicated by the fact that we can no
longer just copy a dfops pointer from the old transaction to the new
transaction. This is solved through a dfops move helper that
transfers the pending items and other dfops state across the
transactions. This also requires that transaction rolling code
always refer to the transaction for the current dfops reference.

Finally, to facilitate incremental conversion to the internal dfops
and continue to support the current external dfops mode of
operation, create the new ->t_dfops_internal field with a layer of
indirection. On allocation, ->t_dfops points to the internal dfops.
This state is overridden by callers who re-init a local dfops on the
transaction. Once ->t_dfops is overridden, the external dfops
reference is maintained as the transaction rolls.

This patch adds the fundamental ability to support an internal
dfops. All codepaths that perform deferred processing continue to
override the internal dfops until they are converted over in
subsequent patches.
Signed-off-by: NBrian Foster <bfoster@redhat.com>
Reviewed-by: NBill O'Donnell <billodo@redhat.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NDarrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: NDarrick J. Wong <darrick.wong@oracle.com>
      e021a2e5
  17. 12 7月, 2018 2 次提交
  19. 25 6月, 2018 1 次提交
  21. 07 6月, 2018 1 次提交
    • D
      xfs: convert to SPDX license tags · 0b61f8a4
      由 Dave Chinner 提交于 
      Remove the verbose license text from XFS files and replace them
with SPDX tags. This does not change the license of any of the code,
merely refers to the common, up-to-date license files in LICENSES/

This change was mostly scripted. fs/xfs/Makefile and
fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected
and modified by the following command:

for f in `git grep -l "GNU General" fs/xfs/` ; do
	echo $f
	cat $f | awk -f hdr.awk > $f.new
	mv -f $f.new $f
done

And the hdr.awk script that did the modification (including
detecting the difference between GPL-2.0 and GPL-2.0+ licenses)
is as follows:

$ cat hdr.awk
BEGIN {
	hdr = 1.0
	tag = "GPL-2.0"
	str = ""
}

/^ \* This program is free software/ {
	hdr = 2.0;
	next
}

/any later version./ {
	tag = "GPL-2.0+"
	next
}

/^ \*\// {
	if (hdr > 0.0) {
		print "// SPDX-License-Identifier: " tag
		print str
		print $0
		str=""
		hdr = 0.0
		next
	}
	print $0
	next
}

/^ \* / {
	if (hdr > 1.0)
		next
	if (hdr > 0.0) {
		if (str != "")
			str = str "\n"
		str = str $0
		next
	}
	print $0
	next
}

/^ \*/ {
	if (hdr > 0.0)
		next
	print $0
	next
}

// {
	if (hdr > 0.0) {
		if (str != "")
			str = str "\n"
		str = str $0
		next
	}
	print $0
}

END { }
$
Signed-off-by: NDave Chinner <dchinner@redhat.com>
Reviewed-by: NDarrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: NDarrick J. Wong <darrick.wong@oracle.com>
      0b61f8a4
  23. 10 5月, 2018 4 次提交
    • D
      xfs: get rid of the log item descriptor · e6631f85
      由 Dave Chinner 提交于 
      It's just a connector between a transaction and a log item. There's
a 1:1 relationship between a log item descriptor and a log item,
and a 1:1 relationship between a log item descriptor and a
transaction. Both relationships are created and terminated at the
same time, so why do we even have the descriptor?

Replace it with a specific list_head in the log item and a new
log item dirtied flag to replace the XFS_LID_DIRTY flag.
Signed-Off-By: NDave Chinner <dchinner@redhat.com>
Reviewed-by: NBrian Foster <bfoster@redhat.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
[darrick: fix up deferred agfl intent finish_item use of LID_DIRTY]
Reviewed-by: NDarrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: NDarrick J. Wong <darrick.wong@oracle.com>
      e6631f85
    • D
      xfs: add tracing to high level transaction operations · ba18781b
      由 Dave Chinner 提交于 
      Because currently we have no idea what the transaction context we
are operating in is, and I need to know that information to track
down bugs in multiple log item joins to transactions.
Signed-Off-By: NDave Chinner <dchinner@redhat.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NBrian Foster <bfoster@redhat.com>
Reviewed-by: NDarrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: NDarrick J. Wong <darrick.wong@oracle.com>
      ba18781b
    • D
      xfs: log item flags are racy · 22525c17
      由 Dave Chinner 提交于 
      The log item flags contain a field that is protected by the AIL
lock - the XFS_LI_IN_AIL flag. We use non-atomic RMW operations to
set and clear these flags, but most of the updates and checks are
not done with the AIL lock held and so are susceptible to update
races.

Fix this by changing the log item flags to use atomic bitops rather
than be reliant on the AIL lock for update serialisation.
Signed-Off-By: NDave Chinner <dchinner@redhat.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NBrian Foster <bfoster@redhat.com>
Reviewed-by: NDarrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: NDarrick J. Wong <darrick.wong@oracle.com>
      22525c17
    • B
      xfs: defer agfl block frees when dfops is available · f8f2835a
      由 Brian Foster 提交于 
      The AGFL fixup code executes before every block allocation/free and
rectifies the AGFL based on the current, dynamic allocation
requirements of the fs. The AGFL must hold a minimum number of
blocks to satisfy a worst case split of the free space btrees caused
by the impending allocation operation. The AGFL is also updated to
maintain the implicit requirement for a minimum number of free slots
to satisfy a worst case join of the free space btrees.

Since the AGFL caches individual blocks, AGFL reduction typically
involves multiple, single block frees. We've had reports of
transaction overrun problems during certain workloads that boil down
to AGFL reduction freeing multiple blocks and consuming more space
in the log than was reserved for the transaction.

Since the objective of freeing AGFL blocks is to ensure free AGFL
free slots are available for the upcoming allocation, one way to
address this problem is to release surplus blocks from the AGFL
immediately but defer the free of those blocks (similar to how
file-mapped blocks are unmapped from the file in one transaction and
freed via a deferred operation) until the transaction is rolled.
This turns AGFL reduction into an operation with predictable log
reservation consumption.

Add the capability to defer AGFL block frees when a deferred ops
list is available to the AGFL fixup code. Add a dfops pointer to the
transaction to carry dfops through various contexts to the allocator
context. Deferring AGFL frees is  conditional behavior based on
whether the transaction pointer is populated. The long term
objective is to reuse the transaction pointer to clean up all
unrelated callchains that pass dfops on the stack along with a
transaction and in doing so, consistently defer AGFL blocks from the
allocator.

A bit of customization is required to handle deferred completion
processing because AGFL blocks are accounted against a per-ag
reservation pool and AGFL blocks are not inserted into the extent
busy list when freed (they are inserted when used and released back
to the AGFL). Reuse the majority of the existing deferred extent
free infrastructure and customize it appropriately to handle AGFL
blocks.

Note that this patch only adds infrastructure. It does not change
behavior because no callers have been updated to pass ->t_agfl_dfops
into the allocation code.
Signed-off-by: NBrian Foster <bfoster@redhat.com>
Reviewed-by: NDarrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: NDarrick J. Wong <darrick.wong@oracle.com>
      f8f2835a
  25. 15 3月, 2018 1 次提交
  27. 12 3月, 2018 2 次提交
    • B
      xfs: shutdown if block allocation overruns tx reservation · 3e78b9a4
      由 Brian Foster 提交于 
      The ->t_blk_res_used field tracks how many blocks have been used in
the current transaction. This should never exceed the block
reservation (->t_blk_res) for a particular transaction. We currently
assert this condition in the transaction block accounting code, but
otherwise take no additional action should this situation occur.

The overrun generally has no effect if space ends up being available
and the associated transaction commits. If the transaction is
duplicated, however, the current block usage is used to determine
the remaining block reservation to be transferred to the new
transaction. If usage exceeds reservation, this calculation
underflows and creates a transaction with an invalid and excessive
reservation. When the second transaction commits, the release of
unused blocks corrupts the in-core free space counters. With lazy
superblock accounting enabled, this inconsistency eventually
trickles to the on-disk superblock and corrupts the filesystem.

Replace the transaction block usage accounting assert with an
explicit overrun check. If the transaction overruns the reservation,
shutdown the filesystem immediately to prevent corruption. Add a new
assert to xfs_trans_dup() to catch any callers that might induce
this invalid state in the future.
Signed-off-by: NBrian Foster <bfoster@redhat.com>
Reviewed-by: NDarrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: NDarrick J. Wong <darrick.wong@oracle.com>
      3e78b9a4
    • M
      xfs: Rename xa_ elements to ail_ · 57e80956
      由 Matthew Wilcox 提交于 
      This is a simple rename, except that xa_ail becomes ail_head.
Signed-off-by: NMatthew Wilcox <mawilcox@microsoft.com>
Reviewed-by: NDarrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: NDarrick J. Wong <darrick.wong@oracle.com>
      57e80956
  29. 09 1月, 2018 1 次提交
  31. 02 9月, 2017 1 次提交
  33. 04 5月, 2017 1 次提交
  35. 07 4月, 2017 1 次提交
  37. 04 4月, 2017 1 次提交
  39. 19 9月, 2016 1 次提交
    • D
      xfs: set up per-AG free space reservations · 3fd129b6
      由 Darrick J. Wong 提交于 
      One unfortunate quirk of the reference count and reverse mapping
btrees -- they can expand in size when blocks are written to *other*
allocation groups if, say, one large extent becomes a lot of tiny
extents.  Since we don't want to start throwing errors in the middle
of CoWing, we need to reserve some blocks to handle future expansion.
The transaction block reservation counters aren't sufficient here
because we have to have a reserve of blocks in every AG, not just
somewhere in the filesystem.

Therefore, create two per-AG block reservation pools.  One feeds the
AGFL so that rmapbt expansion always succeeds, and the other feeds all
other metadata so that refcountbt expansion never fails.

Use the count of how many reserved blocks we need to have on hand to
create a virtual reservation in the AG.  Through selective clamping of
the maximum length of allocation requests and of the length of the
longest free extent, we can make it look like there's less free space
in the AG unless the reservation owner is asking for blocks.

In other words, play some accounting tricks in-core to make sure that
we always have blocks available.  On the plus side, there's nothing to
clean up if we crash, which is contrast to the strategy that the rough
draft used (actually removing extents from the freespace btrees).
Signed-off-by: NDarrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: NDave Chinner <dchinner@redhat.com>
Signed-off-by: NDave Chinner <david@fromorbit.com>
      3fd129b6
  41. 14 9月, 2016 1 次提交